Science

4 deadly diseases we've wiped off the Earth

These days, we don’t worry much about contracting things like polio or smallpox. But it wasn’t all that long ago that diseases like this posed a very real danger to society.

We’re fortunate that advances in medicine, technology, and vaccines have significantly diminished — and in some cases eradicated — outbreaks of some of the world’s most deadly diseases.

Here is a roundup of four deadly diseases that have either been wiped off the earth or are much easier to fight today.

Diphtheria

Photo of young boy grabbing enflamed neck
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These days, diphtheria is relatively little known. However, this highly contagious disease was once a leading cause of death among children. It created a false membrane in the throat that prevented breathing and swallowing, and it could lead to potentially fatal heart and nerve damage.

In 1921, the U.S. recorded 206,000 cases of diphtheria, leading to 15,520 deaths. However, when vaccines were introduced starting in the 1920s, the rates dramatically decreased. By 1974, the diphtheria vaccination was on a suggested list of immunizations for developing countries, decreasing the rate even further.

While the disease does still exist globally, it’s much less of a threat today, and between 2004 and 2017, only two cases of diphtheria were reported in the U.S.

Polio

Young boy getting a polio vaccine
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Short for poliomyelitis, polio is an extremely infectious disease that can lead to lifelong paralysis and even death. As recently as the 1950s, it was one of the most dreaded diseases in the U.S. In 1952, up to 60,000 cases of polio were reported, leading to about 3,000 deaths and many more cases of paralysis.

However, in the later 1950s, several vaccines were introduced to the public. By 1963, polio cases had fallen to 100, and by the 70s, less than 10 cases. No cases have originated in the U.S. since 1979.

While polio has not been eradicated yet, it has been deemed eradicable, and is definitely not considered the threat that it once was.

Rubella

Vials of triple viral vaccine of measles, rubella and mumps
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Rubella is derived from Latin, and means “little red.” At first, it was thought to be a disease related to measles or scarlet fever, but it was eventually classified as a separate disease. It can affect the body’s organs, causing congenital defects, spontaneous abortion, and even death.

In the 1960s, a rubella epidemic hit the U.S., with over 12 million cases and about 20,000 newborns affected.

In 1969, a vaccine was introduced, and by 1983 there were fewer than 1,000 cases of rubella reported. With the exception of a minor outbreak in the early ‘90s, the disease has diminished steadily, with only 11 cases annually from 2005-2011.

Smallpox

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For a long time, smallpox was considered one of the most devastating diseases on Earth. Evidence of a smallpox-like disease has been discovered as far in the past as the times of ancient Egypt, and it was said to be a catalyst in the decline of the Roman Empire.

In 1796, an English doctor named Edward Jenner experimented with a cure by exposing a young boy to a disease that was related to smallpox. This is seen as the first successful vaccine. With increasing medical advances and awareness, it caught on worldwide.

The last known case of smallpox in the U.S. was reported in 1949, and the last known case globally was in Somalia in 1977. In 1980, smallpox was declared to be eradicated.

Stay healthy!

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While these diseases were once among the most dreaded conditions in the world, they are now far less of a threat than they once were. Thanks to ever-improving medical technology and vaccines, we have fully eradicated smallpox, and we are well on our way to eradicating even more of these once-devastating diseases.